Answer:
if 2 length + 2 width is the perimeter, then 2(L+W)=P. if w is 1/3 of L, then W=1/3L, and from there we work back. half of 48 for just one length and one width, we have 24. we want one-third of length+length, so 4 parts. we are left with L=18 and W=6. 18+6=24, x 2= 48. I'm sorry if this was confusing, but I hope this helps!